This disclosure relates to a bladed spoke wrench that is designed to maintain the orientation of bladed spokes when adjustments are made during the assembly or truing bladed spoke bicycle wheels.
Bladed spokes are used in some bicycle wheels to reduce aerodynamic drag, thus reducing the resistance to forward motion. Wind tunnel studies, as well as theoretical calculations show that bladed spokes permit a bike to go faster for the same power input than round spokes due to the reduction in aerodynamic drag. Another way to reduce aerodynamic drag in a spoked wheel is to reduce the number of spokes used in the wheel design. Simply reducing the number of spokes reduces the load carrying capacity of a wheel. To compensate, changes can be undertaken to increase the load carrying capacity of the wheel. One design change to increase load capacity is to utilize a heavier, stiffer rim. Another is to increase spoke tension. In order to reduce weight, some bladed spokes are made from thinner wire.
One drawback to bladed spokes over conventional round spokes is that they are torsionally more flexible than round spokes of equal cross sectional area. Spokes are placed under torsional loads when the technician is adjusting the spoke nipple during wheel assembly or subsequent truing. Bicycle wheel designs with fewer spokes are often under considerably higher spoke tensions and are also under increased torsional stress during spoke adjustment. This torsional flexibility is inconvenient when truing the wheel, since the technician must turn the spoke wrench, not only to adjust the spoke nipple, but to cover the elastic wind up in the flexible spoke. These torsional stresses, when combined with the tensile stresses in a tension spoke, may exceed the yield strength of the spoke, especially spokes made from thinner wire. Unless the torsional stress or the tensile stress within the spoke is controlled, some spokes may yield and permanently take on a spiral set when adjusted without using means for holding the bladed spoke. In order to control torsional loads during adjustment, tools having serrated jaws such as pliers, are sometimes used. These tools can mar or scratch spokes. Such tools are also less convenient to carry and handle.
In view of the above, it should be appreciated that there is a need for a bladed spoke wrench that limits excessive torsional loads on bladed bicycle spokes, to prevent permanent damage to the spokes from occurring and that is convenient to use. The present disclosure satisfies these and other needs and provides further related advantages.